The invention concerns an aircraft door. More exactly, it concerns a door allowing passengers to access the interior of the aircraft, said door incorporating an emergency evacuation slide.
The invention also concerns an aircraft fitted with at least one door of this type.
On aircraft intended for transporting passengers, the regulations lay down that emergency evacuation slides must be present which are able to allow the rapid evacuation of passengers in the event of an accident.
Emergency evacuation slides are usually constituted by inflatable structures, which are stored in the folded up state, in a location provided for this purpose within the aircraft.
Furthermore, the locations in which the slides are stored are selected in order that, in the event of an accident, the slides are deployed underneath at least some of the exits from the aircraft, able to be opened under accident conditions. These exits may be doors usually used for the loading and unloading of passengers or emergency exits usable only in accident conditions.
The requirements stated above lead aircraft builders either to incorporate the locations for storing the slides in the doors liable to be used in the event of an accident, or to incorporate these locations in the fuselage, just beneath the doors or in fairings, close to the doors.
In the first case, the most commonly used solution consists in housing the emergency evacuation slide under a cover forming a bulge towards the interior of the aircraft, in the lower part of the door. When the door is closed after loading the passengers, the cabin personnel set a system allowing the slide housed in the bottom of the door to be mechanically attached to the threshold of the latter.
In the event of an accident, the slide is therefore attached to the threshold of the door. When the latter is opened, the slide deploys automatically outwards from of the aircraft by inflating when activated by means provided for this purpose, generally under the threshold of the door.
Among the documents which illustrate this mode of storing slides will be cited as examples the documents U.S. Pat. Nos. 3,771,749, 4,106,729, WO-A-84/01140 and WO-A-96/40556.
The particular drawback of this conventional solution is its requirement for the slide to be passed through a slot formed in the bottom of the door, when the latter is opened in an emergency evacuation situation. The time required for the slide to be deployed therefore increases its volume. And this is all the larger the greater the size of the aircraft and, particularly the greater the height of the door relative to the ground. Indeed, the volume of the folded slide increases naturally with its deployed length, which must allow the door threshold to be connected with the ground in all the positions liable to be adopted by the aircraft in the event of an accident.
Furthermore, given that deployment of the slides is usually effected through slots formed in the bottom of the doors, the slides are necessarily stored in housings which are also located in the bottom of the doors. This entails the presence of bulges in the bottom of the doors, into the passenger cabin. These bulges translate into a loss of room and prevent seats from being placed immediately behind doors designed in this way.
Moreover, in the case of very long slides, the volume taken up by the bulges formed at the bottom of the doors may render the mechanisms usually providing the opening of the doors unusable. Indeed, the projection serving to house the slide would then interfere with the door frame. In this circumstance, recourse to another solution is imperative.
It is also known, as shown particularly in the document EP-A-0 518 461, for emergency evacuation slides to be housed in locations incorporated in the aircraft fuselage, underneath door thresholds.
This solution does not have the drawbacks of the previous one since the volume serving to house the slide is dissociated from the door. However, it leads to additional apertures being made in the aircraft fuselage, on the same cross-section as the door apertures. To avoid embrittlement of the aircraft structure at this level, braces have to be provided, which is not without consequence on the mass and the cost of the plane.
Furthermore, the document EP-A-0 009 379 describes an emergency exit allowing evacuation from a building, a boat or an aircraft. It includes a fixed rectangular frame, a housing forming a door, whose lower edge is articulated on the frame and an inflatable slide housed in the casing. Activating a bolt triggers the swivelling of the casing outwards and the inflation of the slide.
The precise object of the invention is an aircraft door whose original design allows it to incorporate an emergency evacuation slide of great length without increasing in an unacceptable way its deployment time, while avoiding having to resort to a separate location, incorporated under the door threshold, in the aircraft fuselage.
According to the invention, this outcome is obtained by means of an aircraft door, including a rigid structure having one face turned outwards from the aircraft, said rigid structure incorporating a housing able to receive an emergency evacuation slide, in a folded up state, characterised in that the housing is delimited, on said face of the rigid structure, by a cover able to open to allow deployment of the slide outwards from the aircraft.
This original design makes it possible to provide a very rapid deployment of the slide, whatever its size, which makes the invention particularly adapted to the case of aircraft of very large size, in which the passenger cabin floor is a long way from the ground.
In a first embodiment of the invention, the housing in which the emergency evacuation slide is stored extends over the greater part of the door surface. This particular arrangement of the housing in which the emergency evacuation slide is folded away, over the greater part of the door surface, allows its thickness to be appreciably reduced, relative to a housing located in the door bottom, for an identical volume. Consequently, there is no significant projection towards the interior of the aircraft.
In this first embodiment of the invention, the housing is delimited to advantage towards the interior of the aircraft by an intermediate bulkhead approximately parallel to the cover, so that the housing has an approximately uniform thickness. Preferably, the housing is also delimited laterally and upwards by an inverted U-shaped frame.
In this case, the cover is to advantage attached to the frame by detachable fixing means so as to be able to be ejected outwards from the aircraft.
The back bulkhead is still an integral part of the rigid door structure. According to circumstances, the frame is also an integral part of the rigid structure or is added to this structure.
Furthermore, tightness means are provided, in a usual way, around the door. According to circumstances, these tightness means may be located either approximately in the extension of the intermediate bulkhead, or approximately in the extension of the cover. This latter solution is preferred, since it allows the aerodynamic noises generated by the cavity formed by the door-fuselage interstice to be reduced.
To advantage, the door also includes a lower stepped edge, comprising a closed inner part and an open outer part, communicating with the volume in which the slide is received and offset downwards relative to the closed inner part, so as to form a step. This arrangement makes it possible to increase slightly the volume available for the slide, without increasing too much the size of the aperture made in the aircraft fuselage.
According to a second embodiment of the invention, the cover is attached to the rigid structure by detachable fixing means and setting de-setting means are provided between a lower edge of the cover and the door threshold.
In this case, the setting de-setting means may include at least one shackle mounted on the lower edge of the cover, a receptacle formed on the door threshold and a hook articulated on the door threshold, so as to be able to trap the shackle between the receptacle and the hook.
As a variant, the setting de-setting means may also include at least one pin mounted on the lower edge of the cover and a slotted latch, swivel mounted on the door threshold, so as to be able to trap said pin in the latch slot.
Furthermore, another object of the invention is an aircraft including at least one door as defined above.